(C) Max Planck Institute for Multidisciplinary Sciences, Göttingen
Oktober 2025:
Prof. Dr. Mojib Latif erhält die Science Communication-Medaille 2025.
Im Rahmen der Wissenschaftsreihe beim Göttinger Literaturherbst verleihen die Göttinger Max-Planck-Institute einmal jährlich die Science Communication-Medaille. Damit zeichnen sie Wissenschaftler*innen aus, die sich in besonderem Maße dafür einsetzen, aktuelle Forschungsergebnisse in die Öffentlichkeit zu tragen.
Veranstalter der Vortragsreihe „Wissenschaft beim Göttinger Literaturherbst“ sind die vier Göttinger Max-Planck-Institute, die Göttinger Literaturherbst GmbH sowie die Niedersächsische Staats- und Universitätsbibliothek.
Oktober 2025:
Neue Veröffentlichung:
Song, Z., Latif, M., Park, W. et al. Southern Ocean influence on Atlantic Meridional Overturning Circulation across climate states. Nat Commun 16, 9230 (2025). https://doi.org/10.1038/s41467-025-64268-3
Abstract:
Various proxy data agree on a shallow Atlantic Meridional Overturning Circulation (AMOC) during the last glacial maximum (LGM), extending down to 2000 m − 2500 m depth, which is similar to the AMOC geometry projected by climate models over the 21st century with rising atmospheric CO2. The AMOC strength in the two climate states is insufficiently constrained. Here the Antarctic Bottom Water (AABW) and North Atlantic Deep Water (NADW) properties from proxy data and climate models are used to investigate their influences on the AMOC. It is primarily the AABW’s potential density that determines the AMOC depth in both the LGM and warming climate. Changes in the potential density of the AABW, and the density contrast between NADW and AABW affect the pathways via which NADW returns to the surface and provide a constraint on AMOC strength. This study emphasizes the importance of the Southern Ocean in the AMOC’s depth and strength across climate states.
September 2025:
Neue Veröffentlichung:
Savita, A., Kjellsson, J., Latif, M., Nnamchi, H. C., & Wahl, S. (2025). Causes of Eurasian winter-cooling during the late 20th and early 21st century. Geophysical Research Letters, 52, e2024GL114140. https://doi.org/10.1029/2024GL114140
Summary:
Using atmospheric-model experiments, we find that intrinsic atmospheric variability is the main driver of the recent pronounced wintertime surface cooling over Eurasia during 1993–2013. More specifically, the leading mode of atmospheric circulation variability over the Atlantic sector known as the North Atlantic Oscillation (NAO) was responsible for the largest portion of the Eurasian cooling. The sea-surface temperature (SST) of the Pacific Ocean also contributed to the cooling, but to a lesser degree than the NAO, whereas the North Atlantic SST had only a modest influence. This study suggests that decadal predictability of Eurasian surface climate could be limited.
The Probability Density Function of the DJF-surface air temperature (SAT) trend for the period 1993–2014, averaged over the region between 60°E–120°E and 45°N–60°N (box shown in Figure 3). (a) Control ensemble (Ctl), the gray bars represent the estimates from the individual members, the blue line is the fitted distribution based on kernel density estimation, and the solid black line depicts the ERA5-SAT trend. The ensemble mean of the Ctl ensemble is indicated by the solid orange line, with the orange dashed lines representing the ±standard deviation (sigma). (b), Fitted Probability Density Functions from the Ctl and the noIPV and noAMV ensembles. The numbers in the legend are the ensemble mean and standard deviation obtained by applying a bootstrapping method. Panels (c, d) show the ensemble mean difference between Ctl and noIPV and noAMV, respectively. Dots indicate statistically significance at the 95% confidence level.
September 2025:
Neue Veröffentlichung:
Liu, Y., Kjellsson, J., Savita, A., and Park, W.: Impact of horizontal resolution and model time step on European precipitation extremes in the OpenIFS 43r3 atmospheric model, Geosci. Model Dev., 18, 5435–5449, https://doi.org/10.5194/gmd-18-5435-2025, 2025
Abstract:
Events of extreme precipitation pose a hazard to many parts of Europe but are typically not well represented in climate models. Here, we evaluate daily extreme precipita- tion over Europe during 1982–2019 in observations (GPCC), reanalysis (ERA5), and a set of atmosphere-only simulations at low (100 km), medium (50 km), and high (25 km) horizon- tal resolution and also at different time steps (i.e., 60, 30, and 15 min) using low resolution (100 km) with identical verti- cal resolutions using OpenIFS (version 43r3). We find that both OpenIFS simulations and reanalysis underestimate the rates of extreme precipitation compared to observations. The biases are largest for the lowest resolution (100 km) and de- crease with higher-horizontal-resolution (50 and 25 km) sim- ulations in all seasons. The sensitivity to horizontal resolu- tion is particularly high in mountain regions (such as the Alps, Scandinavia, Iberian Peninsula), likely linked to the sensitivity of vertical velocity to the representation of to- pography. The sensitivity of precipitation to model resolu- tion increases dramatically with increasing percentiles, with modest biases in the 70th–80th percentile range and large bi- ases above the 99th percentile range. We also find that pre- cipitation above the 99th percentile mostly consists of large- scale precipitation (∼ 80 %) in winter, while in summer it is mostly large-scale precipitation in northern Europe (∼ 70 %) and convective precipitation in southern Europe (∼70%). Convective precipitation is more sensitive to model time step than to horizontal resolution. Large-scale precipitation in- creases significantly with both higher horizontal resolution and a shorter model time step.
European averaged precipitation amounts and RMSEs (referenced to GPCC) for European total precipitation at different percentile ranges (70th–80th, 80th–90th, 90th–95th, 95th–99th, 99th–99.5th, 99.5th–99.9th, and > 99.9th percentile) in ERA5 (black) and OpenIFS simulations (LR60m: magenta, LR30m: orange, LR: red, MR: blue, HR: purple) during 1982–2019. Cross marks are the precipitation amounts. Dots are the RMSE values, and error bars are the 95 % CI.
September 2025:
Neue Veröffentlichung:
Sanderson, B. M., Brovkin, V., Fisher, R. A., Hohn, D., Ilyina, T., Jones, C. D., Koenigk, T., Koven, C., Li, H., Lawrence, D. M., Lawrence, P., Liddicoat, S., MacDougall, A. H., Mengis, N., Nicholls, Z., O'Rourke, E., Romanou, A., Sandstad, M., Schwinger, J., Séférian, R., Sentman, L. T., Simpson, I. R., Smith, C., Steinert, N. J., Swann, A. L. S., Tjiputra, J., and Ziehn, T.: flat10MIP: an emissions-driven experiment to diagnose the climate response to positive, zero and negative CO2 emissions, Geosci. Model Dev., 18, 5699–5724, https://doi.org/10.5194/gmd-18-5699-2025, 2025.
Short Summary:
This study investigates how climate models warm in response to simplified carbon emissions trajectories, refining the understanding of climate reversibility and commitment. Metrics are defined for warming response to cumulative emissions and for the cessation of emissions or ramp-down to net-zero and net-negative levels. Results indicate that previous concentration-driven experiments may have overstated the Zero Emissions Commitment due to emissions rates exceeding historical levels.
Summary results for global mean surface temperature (GMST) response in the trial flat10MIP. Colored lines indicate temperature change from (a) pre-industrial levels to (b, c) T100 yr (the average temperature in years 91–110 in esm-flat10) in each of the participating ESMs. Shaded regions refer to the simple climate models' probabilistic distribution ranging from the 10th to 90th percentiles. This distribution is shown as violin plots for the last time step of each scenario, where the shading shows the full range of results and the vertical line indicates the 10th–90th percentiles, with the median in the center. A 20-year moving average is applied to all time series.
September 2025:
Mündliche Prüfung der Doktorarbeit von Estela Monteiro
Summary:
Over the past century, human activities have caused strong alterations to the climate system. Such changes have been confidently attributed to human activities, and international political efforts have attempted to avoid further impacts by limiting global warming levels. In this sense, highly ambitious emissions mitigation scenarios are a desirable future to be aimed for, with a current need for a rapid political and societal move towards such. Despite a clear benefit, and necessity, of reaching such scenarios, uncertainty remains regarding potential system responses as the importance of carbon forcing decreases. Even if these uncertainties should not halt decision-making towards such kinds of future scenarios, a better understanding of the expected responses will allow society to properly assess needed and possible outcomes from our current, and past, decisions.
A first result of this thesis shows that varying aerosols spatial implementation in an intermediate complexity model allows for a considerable surface temperature variability, as well as variability in individual components’, such as land carbon uptake and ocean heat uptake, contributions to the warming or cooling of the system. Triggered feedbacks due to aerosols implementations can have a crucial impact in assessing highly ambitious mitigation scenarios, and should be accounted for by the tools used to study such scenarios.
Furthermore, the presentation introduced the use of a new framework (FROT: Framework for Radiative cOntributions to Temperature responses), to comprehensively assess the temperature variability simulated by distinct models for different ambitious mitigation future scenarios, and to account for individual contributions from different climate components. The findings corroborate the need for including forcings and transient responses when assessing climate development, and show that different sets of climate contributions allow for temperature stabilisation.
Finally, the work here has focused on techniques with the potential to remove carbon dioxide from the atmosphere. It found that for centennial timescales dissolved ocean oxygen, in terms of its total global content, is unable to return to pre-industrial levels. This response, however, is highly dependent on the region and depth considered. While oxygen solubility appears to play a role in controlling the responses in the upper ocean, the findings indicate that apparent oxygen use dominates the simulated oxygen development, especially related to changes in circulation and ventilation.
The reported findings widen the understanding of the range of expected responses and components development under highly ambitious emissions mitigation scenarios, either by reducing or by clarifying different uncertainties expected in the assessment, analysis and potential real-world outcomes of these scenarios. The conclusions here can provide meaningful information to not only improve science understanding, but also inform political and societal decision-making processes.
September 2025:
Neue Veröffentlichung:
Mojib Latif (Hg). 2025: Facetten der Freiheit - Perspektiven auf ein Grundrecht. Herder Verlag, 240 S
Die vielen Gesichter der Freiheit
Bedroht der Klimawandel die Freiheit? Was bedeuten freie Märkte für den Menschen? Ist das geeinte Europa ein Hort der Freiheit? Macht uns die Künstliche Intelligenz wirklich frei? Wie frei sind Gedanken in totalitären Systemen? Und lässt sich Freiheit überhaupt messen? Diesen und anderen Fragen gehen renommierte Forscherinnen und Forscher aus Natur- und Geisteswissenschaften im neuen Band der Essay-Reihe der Akademie der Wissenschaften in Hamburg nach. Sie zeigen: Der Begriff der Freiheit birgt viele Dimensionen.
